Motor-driven surgical cutting and fastening instrument with tactile position feedback

ABSTRACT

A surgical cutting and fastening instrument is disclosed. According to various embodiments, the instrument includes an end effector comprising an elongate channel, a clamping member pivotably connected to the channel, and a moveable cutting instrument for traversing the channel to cut an object clamped in the end effector by the clamping member when the clamping member is in a clamped position. The instrument may also comprise a main drive shaft assembly for actuating the cutting instrument in the end effector, a gear drive train connected to the main drive shaft assembly, and a motor for actuating the gear drive train. The instrument may also includes a closure trigger and a firing trigger, separate from the closure trigger, for actuating the motor when the firing trigger is retracted. Also, the instrument may comprise a mechanical closure system connected to the closure trigger and to the clamping member for causing the clamping member to pivot to the clamped position when the closure trigger is retracted.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation application claiming priority under 35 U.S.C. § 120 to U.S. patent application Ser. No. 15/093,028, entitled MOTOR-DRIVEN FASTENING ASSEMBLY, filed Apr. 7, 2016, now U.S. Patent Application Publication No. 2016/0220249, which is a continuation application claiming priority under 35 U.S.C. § 120 to U.S. patent application Ser. No. 13/656,257, entitled MOTOR-DRIVEN SURGICAL CUTTING AND FASTENING INSTRUMENT WITH TACTILE POSITION FEEDBACK, filed Oct. 19, 2012, which issued on Jun. 21, 2016 as U.S. Pat. No. 9,370,358, which is a continuation application claiming priority under 35 U.S.C. § 120 to Ser. No. 13/151,501, entitled MOTOR-DRIVEN SURGICAL CUTTING AND FASTENING INSTRUMENT WITH TACTILE POSITION FEEDBACK, filed Jun. 2, 2011, which issued on Oct. 23, 2012 as U.S. Pat. No. 8,292,155, which is a continuation application claiming priority under 35 U.S.C. § 120 to U.S. patent application Ser. No. 11/344,024, entitled MOTOR-DRIVEN SURGICAL CUTTING AND FASTENING INSTRUMENT WITH MECHANICAL CLOSURE SYSTEM, filed Jan. 31, 2006, which issued on May 29, 2012 as U.S. Pat. No. 8,186,555, the entire disclosures of which are hereby incorporated by reference herein.

The present application is also related to the following U.S. patent applications, filed on Jan. 31, 2006, which are incorporated herein by reference:

MOTOR-DRIVEN SURGICAL CUTTING AND FASTENING INSTRUMENT WITH USER FEEDBACK SYSTEM; U.S. patent application Ser. No. 11/343,498, now U.S. Pat. No. 7,766,210;

MOTOR-DRIVEN SURGICAL CUTTING AND FASTENING INSTRUMENT WITH LOADING FORCE FEEDBACK; U.S. patent application Ser. No. 11/343,573, now U.S. Pat. No. 7,416,101;

MOTOR-DRIVEN SURGICAL CUTTING AND FASTENING INSTRUMENT WITH TACTILE POSITION FEEDBACK; U.S. patent application Ser. No. 11/344,035, now U.S. Pat. No. 7,422,139;

MOTOR-DRIVEN SURGICAL CUTTING AND FASTENING INSTRUMENT WITH ADAPTIVE USER FEEDBACK; U.S. patent application Ser. No. 11/343,447, now U.S. Pat. No. 7,770,775;

MOTOR-DRIVEN SURGICAL CUTTING AND FASTENING INSTRUMENT WITH ARTICULATABLE END EFFECTOR; U.S. patent application Ser. No. 11/343,562, now U.S. Pat. No. 7,568,603;

SURGICAL CUTTING AND FASTENING INSTRUMENT WITH CLOSURE TRIGGER LOCKING MECHANISM; U.S. patent application Ser. No. 11/343,321, now U.S. Patent Application Publication No. 2007/0175955;

GEARING SELECTOR FOR A POWERED SURGICAL CUTTING AND FASTENING STAPLING INSTRUMENT; U.S. patent application Ser. No. 11/343,563, now U.S. Patent Application Publication No. 2007/0175951;

SURGICAL INSTRUMENT HAVING RECORDING CAPABILITIES; U.S. patent application Ser. No. 11/343,803, now U.S. Pat. No. 7,845,537;

SURGICAL INSTRUMENT HAVING A REMOVABLE BATTERY; U.S. patent application Ser. No. 11/344,020, U.S. Pat. No. 7,464,846;

ELECTRONIC LOCKOUTS AND SURGICAL INSTRUMENT INCLUDING SAME; U.S. patent application Ser. No. 11/343,439, now U.S. Pat. No. 7,644,848;

ENDOSCOPIC SURGICAL INSTRUMENT WITH A HANDLE THAT CAN ARTICULATE WITH RESPECT TO THE SHAFT; U.S. patent application Ser. No. 11/343,547, now U.S. Pat. No. 7,753,904;

ELECTRO-MECHANICAL SURGICAL CUTTING AND FASTENING INSTRUMENT HAVING A ROTARY FIRING AND CLOSURE SYSTEM WITH PARALLEL CLOSURE AND ANVIL ALIGNMENT COMPONENTS; U.S. patent application Ser. No. 11/344,021, now U.S. Pat. No. 7,464,849;

DISPOSABLE STAPLE CARTRIDGE HAVING AN ANVIL WITH TISSUE LOCATOR FOR USE WITH A SURGICAL CUTTING AND FASTENING INSTRUMENT AND MODULAR END EFFECTOR SYSTEM THEREFORE; U.S. patent application Ser. No. 11/343,546, now U.S. Patent Application Publication No. 2007/0175950; and

SURGICAL INSTRUMENT HAVING A FEEDBACK SYSTEM; U.S. patent application Ser. No. 11/343,545, now U.S. Pat. No. 8,708,213.

BACKGROUND

The present invention generally concerns surgical cutting and fastening instruments and, more particularly, motor-driven surgical cutting and fastening instruments.

DRAWINGS

Various embodiments of the present invention are described herein by way of example in conjunction with the following figures, wherein

FIGS. 1 and 2 are perspective views of a surgical cutting and fastening instrument according to various embodiments of the present invention;

FIGS. 3-5 are exploded views of an end effector and shaft of the instrument according to various embodiments of the present invention;

FIG. 6 is a side view of the end effector according to various embodiments of the present invention;

FIG. 7 is an exploded view of the handle of the instrument according to various embodiments of the present invention;

FIGS. 8 and 9 are partial perspective views of the handle according to various embodiments of the present invention;

FIG. 10 is a side view of the handle according to various embodiments of the present invention;

FIG. 11 is a schematic diagram of a circuit used in the instrument according to various embodiments of the present invention;

FIGS. 12-13 are side views of the handle according to other embodiments of the present invention;

FIGS. 14-22 illustrate different mechanisms for locking the closure trigger according to various embodiments of the present invention;

FIGS. 23A-B show a universal joint (“u-joint”) that may be employed at the articulation point of the instrument according to various embodiments of the present invention;

FIGS. 24A-B shows a torsion cable that may be employed at the articulation point of the instrument according to various embodiments of the present invention;

FIGS. 25-31 illustrate a surgical cutting and fastening instrument with power assist according to another embodiment of the present invention;

FIGS. 32-36 illustrate a surgical cutting and fastening instrument with power assist according to yet another embodiment of the present invention;

FIGS. 37-40 illustrate a surgical cutting and fastening instrument with tactile feedback to embodiments of the present invention;

FIGS. 41-42 illustrate a proportional sensor that may be used according to various embodiments of the present invention;

FIG. 43 is a perspective view of a surgical cutting and fastening instrument that can employ various end effector embodiments and staple cartridge embodiments of the present invention;

FIG. 44 is a perspective view of an end effector embodiment of the present invention in a closed position;

FIG. 45 is a perspective view of the end effector of FIG. 44 in an open position;

FIG. 46 is an exploded assembly view of an end effector embodiment of the present invention;

FIG. 47 is a cross sectional view of an end effector embodiment of the present invention supporting a staple cartridge therein with some of the components thereof omitted for clarity;

FIG. 48 is a partial top view of a staple cartridge that may be employed in connection with various embodiments of the present invention;

FIG. 49 is a partial cross-sectional view of a staple cartridge and end effector embodiment of the present invention illustrating the firing of staples into tissue clamped in the end effector;

FIG. 50 is a bottom perspective view of a portion of an end effector embodiment of the present invention supporting a staple cartridge therein;

FIG. 51 is a partial perspective view of an end effector embodiment of the present invention supporting a staple cartridge therein;

FIG. 52 is a perspective view of a distal drive shaft portion of various embodiments of the present invention;

FIG. 53 is a cross-sectional view of the distal drive shaft portion of FIG. 52;

FIG. 54 is a cross-sectional view of the distal drive shaft portion and closure nut with the closure nut in an open position;

FIG. 55 is another cross-sectional view of the distal drive shaft portion and closure nut with the closure nut in the closed position;

FIG. 56 is a perspective view of a tapered clutch member of various embodiments of the present invention;

FIG. 57 is a cross-sectional view of the tapered clutch member of FIG. 56;

FIG. 58 is a perspective view of a clutch plate of various embodiments of the present invention;

FIG. 59 is a cross-sectional view of the clutch plate of FIG. 58;

FIG. 60 is a perspective view of a closure nut of various embodiments of the present invention;

FIG. 61 is a cross-sectional view of the closure nut of FIG. 60;

FIG. 62 is a side elevational view of various end effector embodiments of the present invention in an open position;

FIG. 63 is an enlarged partial cut away view of the end effector of FIG. 62;

FIG. 64 is another enlarged partial cutaway view of the end effector of FIG. 62;

FIG. 65 is a side elevational view of an end effector of the present invention in an open position clamping a piece of tissue therein;

FIG. 66 is an enlarged partial cut away view of the end effector of FIG. 65;

FIG. 67 is a side elevational view of various end effector embodiments of the present invention prior to being actuated to a closed position;

FIG. 68 is an enlarged partial cut away view of the end effector of FIG. 67;

FIG. 69 is a side elevational view of various end effector embodiments of the present invention in a closed position;

FIG. 70 is an enlarged partial cut away view of the end effector of FIG. 69;

FIG. 71 is another enlarged partial cut away view of the end effector of FIGS. 69 and 70;

FIG. 72 is a cross-sectional view of the end effector of FIGS. 69-71 after the knife assembly has been driven to its distal-most position;

FIG. 73 is a cross-sectional view of the end effector of FIGS. 69-71;

FIG. 74 is a partial enlarged view of a portion of an end effector of the present invention;

FIG. 75 is a cross-sectional view of a control handle of various embodiments of the present invention;

FIG. 76 is a partial cross-sectional view of a portion of another end effector embodiment of the present invention in an open position; and

FIG. 77 is a partial cross-sectional view of the end effector of FIG. 76 in a closed position.

DETAILED DESCRIPTION

FIGS. 1 and 2 depict a surgical cutting and fastening instrument 10 according to various embodiments of the present invention. The illustrated embodiment is an endoscopic instrument and, in general, the embodiments of the instrument 10 described herein are endoscopic surgical cutting and fastening instruments. It should be noted, however, that according to other embodiments of the present invention, the instrument may be a non-endoscopic surgical cutting and fastening instrument, such as a laparoscopic instrument.

The surgical instrument 10 depicted in FIGS. 1 and 2 comprises a handle 6, a shaft 8, and an articulating end effector 12 pivotally connected to the shaft 8 at an articulation pivot 14. An articulation control 16 may be provided adjacent to the handle 6 to effect rotation of the end effector 12 about the articulation pivot 14. In the illustrated embodiment, the end effector 12 is configured to act as an endocutter for clamping, severing and stapling tissue, although, in other embodiments, different types of end effectors may be used, such as end effectors for other types of surgical devices, such as graspers, cutters, staplers, clip appliers, access devices, drug/gene therapy devices, ultrasound, RF or laser devices, etc.

The handle 6 of the instrument 10 may include a closure trigger 18 and a firing trigger 20 for actuating the end effector 12. It will be appreciated that instruments having end effectors directed to different surgical tasks may have different numbers or types of triggers or other suitable controls for operating the end effector 12. The end effector 12 is shown separated from the handle 6 by a preferably elongate shaft 8. In one embodiment, a clinician or operator of the instrument 10 may articulate the end effector 12 relative to the shaft 8 by utilizing the articulation control 16, as described in more detail in U.S. patent application Ser. No. 11/329,020, filed Jan. 10, 2006, entitled SURGICAL INSTRUMENT HAVING AN ARTICULATING END EFFECTOR, now U.S. Pat. No. 7,670,334, which is incorporated herein by reference.

The end effector 12 includes in this example, among other things, a staple channel 22 and a pivotally translatable clamping member, such as an anvil 24, which are maintained at a spacing that assures effective stapling and severing of tissue clamped in the end effector 12. The handle 6 includes a pistol grip 26 towards which a closure trigger 18 is pivotally drawn by the clinician to cause clamping or closing of the anvil 24 toward the staple channel 22 of the end effector 12 to thereby clamp tissue positioned between the anvil 24 and channel 22. The firing trigger 20 is farther outboard of the closure trigger 18. Once the closure trigger 18 is locked in the closure position as further described below, the firing trigger 20 may rotate slightly toward the pistol grip 26 so that it can be reached by the operator using one hand. Then the operator may pivotally draw the firing trigger 20 toward the pistol grip 12 to cause the stapling and severing of clamped tissue in the end effector 12. In other embodiments, different types of clamping members besides the anvil 24 could be used, such as, for example, an opposing jaw, etc.

It will be appreciated that the terms “proximal” and “distal” are used herein with reference to a clinician gripping the handle 6 of an instrument 10. Thus, the end effector 12 is distal with respect to the more proximal handle 6. It will be further appreciated that, for convenience and clarity, spatial terms such as “vertical” and “horizontal” are used herein with respect to the drawings. However, surgical instruments are used in many orientations and positions, and these terms are not intended to be limiting and absolute.

The closure trigger 18 may be actuated first. Once the clinician is satisfied with the positioning of the end effector 12, the clinician may draw back the closure trigger 18 to its fully closed, locked position proximate to the pistol grip 26. The firing trigger 20 may then be actuated. The firing trigger 20 returns to the open position (shown in FIGS. 1 and 2) when the clinician removes pressure, as described more fully below. A release button on the handle 6, when depressed may release the locked closure trigger 18. The release button may be implemented in various forms such as, for example, as a slide release button 160 shown in FIG. 14, and/or button 172 shown in FIG. 16.

FIG. 3 is an exploded view of the end effector 12 according to various embodiments. As shown in the illustrated embodiment, the end effector 12 may include, in addition to the previously-mentioned channel 22 and anvil 24, a cutting instrument 32, a sled 33, a staple cartridge 34 that is removably seated in the channel 22, and a helical screw shaft 36. The cutting instrument 32 may be, for example, a knife. The anvil 24 may be pivotably opened and closed at a pivot point 25 connected to the proximate end of the channel 22. The anvil 24 may also include a tab 27 at its proximate end that is inserted into a component of the mechanical closure system (described further below) to open and close the anvil 24. When the closure trigger 18 is actuated, that is, drawn in by a user of the instrument 10, the anvil 24 may pivot about the pivot point 25 into the clamped or closed position. If clamping of the end effector 12 is satisfactory, the operator may actuate the firing trigger 20, which, as explained in more detail below, causes the knife 32 and sled 33 to travel longitudinally along the channel 22, thereby cutting tissue clamped within the end effector 12. The movement of the sled 33 along the channel 22 causes the staples of the staple cartridge 34 to be driven through the severed tissue and against the closed anvil 24, which turns the staples to fasten the severed tissue. In various embodiments, the sled 33 may be an integral component of the cartridge 34. U.S. Pat. No. 6,978,921, entitled SURGICAL STAPLING INSTRUMENT INCORPORATING AN E-BEAM FIRING MECHANISM, which is incorporated herein by reference, provides more details about such two-stroke cutting and fastening instruments. The sled 33 may be part of the cartridge 34, such that when the knife 32 retracts following the cutting operation, the sled 33 does not retract.

It should be noted that although the embodiments of the instrument 10 described herein employ an end effector 12 that staples the severed tissue, in other embodiments different techniques for fastening or sealing the severed tissue may be used. For example, end effectors that use RF energy or adhesives to fasten the severed tissue may also be used. U.S. Pat. No. 5,709,680 entitled ELECTROSURGICAL HEMOSTATIC DEVICE, and U.S. Pat. No. 5,688,270 entitled ELECTROSURGICAL HEMOSTATIC DEVICE WITH RECESSED AND/OR OFFSET ELECTRODES, which are incorporated herein by reference, disclose an endoscopic cutting instrument that uses RF energy to seal the severed tissue. U.S. patent application Ser. No. 11/267,811, now U.S. Pat. No. 7,673,783, and U.S. patent application Ser. No. 11/267,383, now U.S. Pat. No. 7,607,557, which are also incorporated herein by reference, disclose an endoscopic cutting instrument that uses adhesives to fasten the severed tissue. Accordingly, although the description herein refers to cutting/stapling operations and the like below, it should be recognized that this is an exemplary embodiment and is not meant to be limiting. Other tissue-fastening techniques may also be used.

FIGS. 4 and 5 are exploded views and FIG. 6 is a side view of the end effector 12 and shaft 8 according to various embodiments. As shown in the illustrated embodiment, the shaft 8 may include a proximate closure tube 40 and a distal closure tube 42 pivotably linked by a pivot links 44. The distal closure tube 42 includes an opening 45 into which the tab 27 on the anvil 24 is inserted in order to open and close the anvil 24, as further described below. Disposed inside the closure tubes 40, 42 may be a proximate spine tube 46. Disposed inside the proximate spine tube 46 may be a main rotational (or proximate) drive shaft 48 that communicates with a secondary (or distal) drive shaft 50 via a bevel gear assembly 52. The secondary drive shaft 50 is connected to a drive gear 54 that engages a proximate drive gear 56 of the helical screw shaft 36. The vertical bevel gear 52 b may sit and pivot in an opening 57 in the distal end of the proximate spine tube 46. A distal spine tube 58 may be used to enclose the secondary drive shaft 50 and the drive gears 54, 56. Collectively, the main drive shaft 48, the secondary drive shaft 50, and the articulation assembly (e.g., the bevel gear assembly 52 a-c) are sometimes referred to herein as the “main drive shaft assembly.”

A bearing 38, positioned at a distal end of the staple channel 22, receives the helical drive screw 36, allowing the helical drive screw 36 to freely rotate with respect to the channel 22. The helical screw shaft 36 may interface a threaded opening (not shown) of the knife 32 such that rotation of the shaft 36 causes the knife 32 to translate distally or proximately (depending on the direction of the rotation) through the staple channel 22. Accordingly, when the main drive shaft 48 is caused to rotate by actuation of the firing trigger 20 (as explained in more detail below), the bevel gear assembly 52 a-c causes the secondary drive shaft 50 to rotate, which in turn, because of the engagement of the drive gears 54, 56, causes the helical screw shaft 36 to rotate, which causes the knife driving member 32 to travel longitudinally along the channel 22 to cut any tissue clamped within the end effector. The sled 33 may be made of, for example, plastic, and may have a sloped distal surface. As the sled 33 traverse the channel 22, the sloped forward surface may push up or drive the staples in the staple cartridge through the clamped tissue and against the anvil 24. The anvil 24 turns the staples, thereby stapling the severed tissue. When the knife 32 is retracted, the knife 32 and sled 33 may become disengaged, thereby leaving the sled 33 at the distal end of the channel 22.

As described above, because of the lack of user feedback for the cutting/stapling operation, there is a general lack of acceptance among physicians of motor-driven endocutters where the cutting/stapling operation is actuated by merely pressing a button. In contrast, embodiments of the present invention provide a motor-driven endocutter with user-feedback of the deployment, force, and/or position of the cutting instrument in the end effector.

FIGS. 7-10 illustrate an exemplary embodiment of a motor-driven endocutter, and in particular the handle thereof, that provides user-feedback regarding the deployment and loading force of the cutting instrument in the end effector. In addition, the embodiment may use power provided by the user in retracting the firing trigger 20 to power the device (a so-called “power assist” mode). As shown in the illustrated embodiment, the handle 6 includes exterior lower side pieces 59, 60 and exterior upper side pieces 61, 62 that fit together to form, in general, the exterior of the handle 6. A battery 64, such as a Li ion battery, may be provided in the pistol grip portion 26 of the handle 6. The battery 64 powers a motor 65 disposed in an upper portion of the pistol grip portion 26 of the handle 6. According to various embodiments, the motor 65 may be a DC brushed driving motor having a maximum rotation of, approximately, 5000 RPM. The motor 64 may drive a 90° bevel gear assembly 66 comprising a first bevel gear 68 and a second bevel gear 70. The bevel gear assembly 66 may drive a planetary gear assembly 72. The planetary gear assembly 72 may include a pinion gear 74 connected to a drive shaft 76. The pinion gear 74 may drive a mating ring gear 78 that drives a helical gear drum 80 via a drive shaft 82. A ring 84 may be threaded on the helical gear drum 80. Thus, when the motor 65 rotates, the ring 84 is caused to travel along the helical gear drum 80 by means of the interposed bevel gear assembly 66, planetary gear assembly 72 and ring gear 78.

The handle 6 may also include a run motor sensor 110 in communication with the firing trigger 20 to detect when the firing trigger 20 has been drawn in (or “closed”) toward the pistol grip portion 26 of the handle 6 by the operator to thereby actuate the cutting/stapling operation by the end effector 12. The sensor 110 may be a proportional sensor such as, for example, a rheostat or variable resistor. When the firing trigger 20 is drawn in, the sensor 110 detects the movement, and sends an electrical signal indicative of the voltage (or power) to be supplied to the motor 65. When the sensor 110 is a variable resistor or the like, the rotation of the motor 65 may be generally proportional to the amount of movement of the firing trigger 20. That is, if the operator only draws or closes the firing trigger 20 in a little bit, the rotation of the motor 65 is relatively low. When the firing trigger 20 is fully drawn in (or in the fully closed position), the rotation of the motor 65 is at its maximum. In other words, the harder the user pulls on the firing trigger 20, the more voltage is applied to the motor 65, causing greater rates of rotation.

The handle 6 may include a middle handle piece 104 adjacent to the upper portion of the firing trigger 20. The handle 6 also may comprise a bias spring 112 connected between posts on the middle handle piece 104 and the firing trigger 20. The bias spring 112 may bias the firing trigger 20 to its fully open position. In that way, when the operator releases the firing trigger 20, the bias spring 112 will pull the firing trigger 20 to its open position, thereby removing actuation of the sensor 110, thereby stopping rotation of the motor 65. Moreover, by virtue of the bias spring 112, any time a user closes the firing trigger 20, the user will experience resistance to the closing operation, thereby providing the user with feedback as to the amount of rotation exerted by the motor 65. Further, the operator could stop retracting the firing trigger 20 to thereby remove force from the sensor 100, to thereby stop the motor 65. As such, the user may stop the deployment of the end effector 12, thereby providing a measure of control of the cutting/fastening operation to the operator.

The distal end of the helical gear drum 80 includes a distal drive shaft 120 that drives a ring gear 122, which mates with a pinion gear 124. The pinion gear 124 is connected to the main drive shaft 48 of the main drive shaft assembly. In that way, rotation of the motor 65 causes the main drive shaft assembly to rotate, which causes actuation of the end effector 12, as described above.

The ring 84 threaded on the helical gear drum 80 may include a post 86 that is disposed within a slot 88 of a slotted arm 90. The slotted arm 90 has an opening 92 its opposite end 94 that receives a pivot pin 96 that is connected between the handle exterior side pieces 59, 60. The pivot pin 96 is also disposed through an opening 100 in the firing trigger 20 and an opening 102 in the middle handle piece 104.

In addition, the handle 6 may include a reverse motor (or end-of-stroke sensor) 130 and a stop motor (or beginning-of-stroke) sensor 142. In various embodiments, the reverse motor sensor 130 may be a limit switch located at the distal end of the helical gear drum 80 such that the ring 84 threaded on the helical gear drum 80 contacts and trips the reverse motor sensor 130 when the ring 84 reaches the distal end of the helical gear drum 80. The reverse motor sensor 130, when activated, sends a signal to the motor 65 to reverse its rotation direction, thereby withdrawing the knife 32 of the end effector 12 following the cutting operation.

The stop motor sensor 142 may be, for example, a normally-closed limit switch. In various embodiments, it may be located at the proximate end of the helical gear drum 80 so that the ring 84 trips the switch 142 when the ring 84 reaches the proximate end of the helical gear drum 80.

In operation, when an operator of the instrument 10 pulls back the firing trigger 20, the sensor 110 detects the deployment of the firing trigger 20 and sends a signal to the motor 65 to cause forward rotation of the motor 65 at, for example, a rate proportional to how hard the operator pulls back the firing trigger 20. The forward rotation of the motor 65 in turn causes the ring gear 78 at the distal end of the planetary gear assembly 72 to rotate, thereby causing the helical gear drum 80 to rotate, causing the ring 84 threaded on the helical gear drum 80 to travel distally along the helical gear drum 80. The rotation of the helical gear drum 80 also drives the main drive shaft assembly as described above, which in turn causes deployment of the knife 32 in the end effector 12. That is, the knife 32 and sled 33 are caused to traverse the channel 22 longitudinally, thereby cutting tissue clamped in the end effector 12. Also, the stapling operation of the end effector 12 is caused to happen in embodiments where a stapling-type end effector is used.

By the time the cutting/stapling operation of the end effector 12 is complete, the ring 84 on the helical gear drum 80 will have reached the distal end of the helical gear drum 80, thereby causing the reverse motor sensor 130 to be tripped, which sends a signal to the motor 65 to cause the motor 65 to reverse its rotation. This in turn causes the knife 32 to retract, and also causes the ring 84 on the helical gear drum 80 to move back to the proximate end of the helical gear drum 80.

The middle handle piece 104 includes a backside shoulder 106 that engages the slotted arm 90 as best shown in FIGS. 8 and 9. The middle handle piece 104 also has a forward motion stop 107 that engages the firing trigger 20. The movement of the slotted arm 90 is controlled, as explained above, by rotation of the motor 65. When the slotted arm 90 rotates CCW as the ring 84 travels from the proximate end of the helical gear drum 80 to the distal end, the middle handle piece 104 will be free to rotate CCW. Thus, as the user draws in the firing trigger 20, the firing trigger 20 will engage the forward motion stop 107 of the middle handle piece 104, causing the middle handle piece 104 to rotate CCW. Due to the backside shoulder 106 engaging the slotted arm 90, however, the middle handle piece 104 will only be able to rotate CCW as far as the slotted arm 90 permits. In that way, if the motor 65 should stop rotating for some reason, the slotted arm 90 will stop rotating, and the user will not be able to further draw in the firing trigger 20 because the middle handle piece 104 will not be free to rotate CCW due to the slotted arm 90.

FIGS. 41 and 42 illustrate two states of a variable sensor that may be used as the run motor sensor 110 according to various embodiments of the present invention. The sensor 110 may include a face portion 280, a first electrode (A) 282, a second electrode (B) 284, and a compressible dielectric material 286 (e.g., EAP) between the electrodes 282, 284. The sensor 110 may be positioned such that the face portion 280 contacts the firing trigger 20 when retracted. Accordingly, when the firing trigger 20 is retracted, the dielectric material 286 is compressed, as shown in FIG. 42, such that the electrodes 282, 284 are closer together. Since the distance “b” between the electrodes 282, 284 is directly related to the impedance between the electrodes 282, 284, the greater the distance the more impedance, and the closer the distance the less impedance. In that way, the amount that the dielectric 286 is compressed due to retraction of the firing trigger 20 (denoted as force “F” in FIG. 42) is proportional to the impedance between the electrodes 282, 284, which can be used to proportionally control the motor 65.

Components of an exemplary closure system for closing (or clamping) the anvil 24 of the end effector 12 by retracting the closure trigger 18 are also shown in FIGS. 7-10. In the illustrated embodiment, the closure system includes a yoke 250 connected to the closure trigger 18 by a pin 251 that is inserted through aligned openings in both the closure trigger 18 and the yoke 250. A pivot pin 252, about which the closure trigger 18 pivots, is inserted through another opening in the closure trigger 18 which is offset from where the pin 251 is inserted through the closure trigger 18. Thus, retraction of the closure trigger 18 causes the upper part of the closure trigger 18, to which the yoke 250 is attached via the pin 251, to rotate CCW. The distal end of the yoke 250 is connected, via a pin 254, to a first closure bracket 256. The first closure bracket 256 connects to a second closure bracket 258. Collectively, the closure brackets 256, 258 define an opening in which the proximate end of the proximate closure tube 40 (see FIG. 4) is seated and held such that longitudinal movement of the closure brackets 256, 258 causes longitudinal motion by the proximate closure tube 40. The instrument 10 also includes a closure rod 260 disposed inside the proximate closure tube 40. The closure rod 260 may include a window 261 into which a post 263 on one of the handle exterior pieces, such as exterior lower side piece 59 in the illustrated embodiment, is disposed to fixedly connect the closure rod 260 to the handle 6. In that way, the proximate closure tube 40 is capable of moving longitudinally relative to the closure rod 260. The closure rod 260 may also include a distal collar 267 that fits into a cavity 269 in proximate spine tube 46 and is retained therein by a cap 271 (see FIG. 4).

In operation, when the yoke 250 rotates due to retraction of the closure trigger 18, the closure brackets 256, 258 cause the proximate closure tube 40 to move distally (i.e., away from the handle end of the instrument 10), which causes the distal closure tube 42 to move distally, which causes the anvil 24 to rotate about the pivot point 25 into the clamped or closed position. When the closure trigger 18 is unlocked from the locked position, the proximate closure tube 40 is caused to slide proximately, which causes the distal closure tube 42 to slide proximately, which, by virtue of the tab 27 being inserted in the window 45 of the distal closure tube 42, causes the anvil 24 to pivot about the pivot point 25 into the open or unclamped position. In that way, by retracting and locking the closure trigger 18, an operator may clamp tissue between the anvil 24 and channel 22, and may unclamp the tissue following the cutting/stapling operation by unlocking the closure trigger 20 from the locked position.

FIG. 11 is a schematic diagram of an electrical circuit of the instrument 10 according to various embodiments of the present invention. When an operator initially pulls in the firing trigger 20 after locking the closure trigger 18, the sensor 110 is activated, allowing current to flow there through. If the normally-open reverse motor sensor switch 130 is open (meaning the end of the end effector stroke has not been reached), current will flow to a single pole, double throw relay 132. Since the reverse motor sensor switch 130 is not closed, the inductor 134 of the relay 132 will not be energized, so the relay 132 will be in its non-energized state. The circuit also includes a cartridge lockout sensor 136. If the end effector 12 includes a staple cartridge 34, the sensor 136 will be in the closed state, allowing current to flow. Otherwise, if the end effector 12 does not include a staple cartridge 34, the sensor 136 will be open, thereby preventing the battery 64 from powering the motor 65.

When the staple cartridge 34 is present, the sensor 136 is closed, which energizes a single pole, single throw relay 138. When the relay 138 is energized, current flows through the relay 136, through the variable resistor sensor 110, and to the motor 65 via a double pole, double throw relay 140, thereby powering the motor 65 and allowing it to rotate in the forward direction.

When the end effector 12 reaches the end of its stroke, the reverse motor sensor 130 will be activated, thereby closing the switch 130 and energizing the relay 134. This causes the relay 134 to assume its energized state (not shown in FIG. 13), which causes current to bypass the cartridge lockout sensor 136 and variable resistor 110, and instead causes current to flow to both the normally-closed double pole, double throw relay 142 and back to the motor 65, but in a manner, via the relay 140, that causes the motor 65 to reverse its rotational direction.

Because the stop motor sensor switch 142 is normally-closed, current will flow back to the relay 134 to keep it closed until the switch 142 opens. When the knife 32 is fully retracted, the stop motor sensor switch 142 is activated, causing the switch 142 to open, thereby removing power from the motor 65.

In other embodiments, rather than a proportional-type sensor 110, an on-off type sensor could be used. In such embodiments, the rate of rotation of the motor 65 would not be proportional to the force applied by the operator. Rather, the motor 65 would generally rotate at a constant rate. But the operator would still experience force feedback because the firing trigger 20 is geared into the gear drive train.

FIG. 12 is a side-view of the handle 6 of a power-assist motorized endocutter according to another embodiment. The embodiment of FIG. 12 is similar to that of FIGS. 7-10 except that in the embodiment of FIG. 12, there is not slotted arm connected to the ring 84 threaded on the helical gear drum 80. Instead, in the embodiment of FIG. 12, the ring 84 includes a sensor portion 114 that moves with the ring 84 as the ring 84 advances down (and back) on the helical gear drum 80. The sensor portion 114 includes a notch 116. The reverse motor sensor 130 may be located at the distal end of the notch 116 and the stop motor sensor 142 may be located at the proximate end of the notch 116. As the ring 84 moves down the helical gear drum 80 (and back), the sensor portion 114 moves with it. Further, as shown in FIG. 12, the middle piece 104 may have an arm 118 that extends into the notch 12.

In operation, as an operator of the instrument 10 retracts in the firing trigger 20 toward the pistol grip 26, the run motor sensor 110 detects the motion and sends a signal to power the motor 65, which causes, among other things, the helical gear drum 80 to rotate. As the helical gear drum 80 rotates, the ring 84 threaded on the helical gear drum 80 advances (or retracts, depending on the rotation). Also, due to the pulling in of the firing trigger 20, the middle piece 104 is caused to rotate CCW with the firing trigger 20 due to the forward motion stop 107 that engages the firing trigger 20. The CCW rotation of the middle piece 104 cause the arm 118 to rotate CCW with the sensor portion 114 of the ring 84 such that the arm 118 stays disposed in the notch 116. When the ring 84 reaches the distal end of the helical gear drum 80, the arm 118 will contact and thereby trip the reverse motor sensor 130. Similarly, when the ring 84 reaches the proximate end of the helical gear drum 80, the arm will contact and thereby trip the stop motor sensor 142. Such actions may reverse and stop the motor 65, respectively, as described above.

FIG. 13 is a side-view of the handle 6 of a power-assist motorized endocutter according to another embodiment. The embodiment of FIG. 13 is similar to that of FIGS. 7-10 except that in the embodiment of FIG. 13, there is no slot in the arm 90. Instead, the ring 84 threaded on the helical gear drum 80 includes a vertical channel 126. Instead of a slot, the arm 90 includes a post 128 that is disposed in the channel 126. As the helical gear drum 80 rotates, the ring 84 threaded on the helical gear drum 80 advances (or retracts, depending on the rotation). The arm 90 rotates CCW as the ring 84 advances due to the post 128 being disposed in the channel 126, as shown in FIG. 13.

As mentioned above, in using a two-stroke motorized instrument, the operator first pulls back and locks the closure trigger 18. FIGS. 14 and 15 show one embodiment of a way to lock the closure trigger 18 to the pistol grip portion 26 of the handle 6. In the illustrated embodiment, the pistol grip portion 26 includes a hook 150 that is biased to rotate CCW about a pivot point 151 by a torsion spring 152. Also, the closure trigger 18 includes a closure bar 154. As the operator draws in the closure trigger 18, the closure bar 154 engages a sloped portion 156 of the hook 150, thereby rotating the hook 150 upward (or CW in FIGS. 12-13) until the closure bar 154 completely passes the sloped portion 156 passes into a recessed notch 158 of the hook 150, which locks the closure trigger 18 in place. The operator may release the closure trigger 18 by pushing down on a slide button release 160 on the back or opposite side of the pistol grip portion 26. Pushing down the slide button release 160 rotates the hook 150 CW such that the closure bar 154 is released from the recessed notch 158.

FIG. 16 shows another closure trigger locking mechanism according to various embodiments. In the embodiment of FIG. 16, the closure trigger 18 includes a wedge 160 having an arrow-head portion 161. The arrow-head portion 161 is biased downward (or CW) by a leaf spring 162. The wedge 160 and leaf spring 162 may be made from, for example, molded plastic. When the closure trigger 18 is retracted, the arrow-head portion 161 is inserted through an opening 164 in the pistol grip portion 26 of the handle 6. A lower chamfered surface 166 of the arrow-head portion 161 engages a lower sidewall 168 of the opening 164, forcing the arrow-head portion 161 to rotate CCW. Eventually the lower chamfered surface 166 fully passes the lower sidewall 168, removing the CCW force on the arrow-head portion 161, causing the lower sidewall 168 to slip into a locked position in a notch 170 behind the arrow-head portion 161.

To unlock the closure trigger 18, a user presses down on a button 172 on the opposite side of the closure trigger 18, causing the arrow-head portion 161 to rotate CCW and allowing the arrow-head portion 161 to slide out of the opening 164.

FIGS. 17-22 show a closure trigger locking mechanism according to another embodiment. As shown in this embodiment, the closure trigger 18 includes a flexible longitudinal arm 176 that includes a lateral pin 178 extending therefrom. The arm 176 and pin 178 may be made from molded plastic, for example. The pistol grip portion 26 of the handle 6 includes an opening 180 with a laterally extending wedge 182 disposed therein. When the closure trigger 18 is retracted, the pin 178 engages the wedge 182, and the pin 178 is forced downward (i.e., the arm 176 is rotated CW) by the lower surface 184 of the wedge 182, as shown in FIGS. 17 and 18. When the pin 178 fully passes the lower surface 184, the CW force on the arm 176 is removed, and the pin 178 is rotated CCW such that the pin 178 comes to rest in a notch 186 behind the wedge 182, as shown in FIG. 19, thereby locking the closure trigger 18. The pin 178 is further held in place in the locked position by a flexible stop 188 extending from the wedge 184.

To unlock the closure trigger 18, the operator may further squeeze the closure trigger 18, causing the pin 178 to engage a sloped backwall 190 of the opening 180, forcing the pin 178 upward past the flexible stop 188, as shown in FIGS. 20 and 21. The pin 178 is then free to travel out an upper channel 192 in the opening 180 such that the closure trigger 18 is no longer locked to the pistol grip portion 26, as shown in FIG. 22.

FIGS. 23A-B show a universal joint (“u-joint”) 195. The second piece 195-2 of the u-joint 195 rotates in a horizontal plane in which the first piece 195-1 lies. FIG. 23A shows the u-joint 195 in a linear (180°) orientation and FIG. 23B shows the u-joint 195 at approximately a 150° orientation. The u-joint 195 may be used instead of the bevel gears 52 a-c (see FIG. 4, for example) at the articulation point 14 of the main drive shaft assembly to articulate the end effector 12. FIGS. 24A-B show a torsion cable 197 that may be used in lieu of both the bevel gears 52 a-c and the u-joint 195 to realize articulation of the end effector 12.

FIGS. 25-31 illustrate another embodiment of a motorized, two-stroke surgical cutting and fastening instrument 10 with power assist according to another embodiment of the present invention. The embodiment of FIGS. 25-31 is similar to that of FIGS. 6-10 except that instead of the helical gear drum 80, the embodiment of FIGS. 23-28 includes an alternative gear drive assembly. The embodiment of FIGS. 25-31 includes a gear box assembly 200 including a number of gears disposed in a frame 201, wherein the gears are connected between the planetary gear 72 and the pinion gear 124 at the proximate end of the drive shaft 48. As explained further below, the gear box assembly 200 provides feedback to the user via the firing trigger 20 regarding the deployment and loading force of the end effector 12. Also, the user may provide power to the system via the gear box assembly 200 to assist the deployment of the end effector 12. In that sense, like the embodiments described above, the embodiment of FIGS. 23-32 is another power assist, motorized instrument 10 that provides feedback to the user regarding the loading force experienced by the cutting instrument.

In the illustrated embodiment, the firing trigger 20 includes two pieces: a main body portion 202 and a stiffening portion 204. The main body portion 202 may be made of plastic, for example, and the stiffening portion 204 may be made out of a more rigid material, such as metal. In the illustrated embodiment, the stiffening portion 204 is adjacent to the main body portion 202, but according to other embodiments, the stiffening portion 204 could be disposed inside the main body portion 202. A pivot pin 209 may be inserted through openings in the firing trigger pieces 202, 204 and may be the point about which the firing trigger 20 rotates. In addition, a spring 222 may bias the firing trigger 20 to rotate in a CCW direction. The spring 222 may have a distal end connected to a pin 224 that is connected to the pieces 202, 204 of the firing trigger 20. The proximate end of the spring 222 may be connected to one of the handle exterior lower side pieces 59, 60.

In the illustrated embodiment, both the main body portion 202 and the stiffening portion 204 includes gear portions 206, 208 (respectively) at their upper end portions. The gear portions 206, 208 engage a gear in the gear box assembly 200, as explained below, to drive the main drive shaft assembly and to provide feedback to the user regarding the deployment of the end effector 12.

The gear box assembly 200 may include as shown, in the illustrated embodiment, six (6) gears. A first gear 210 of the gear box assembly 200 engages the gear portions 206, 208 of the firing trigger 20. In addition, the first gear 210 engages a smaller second gear 212, the smaller second gear 212 being coaxial with a large third gear 214. The third gear 214 engages a smaller fourth gear 216, the smaller fourth gear being coaxial with a fifth gear 218. The fifth gear 218 is a 90° bevel gear that engages a mating 90° bevel gear 220 (best shown in FIG. 31) that is connected to the pinion gear 124 that drives the main drive shaft 48.

In operation, when the user retracts the firing trigger 20, a run motor sensor (not shown) is activated, which may provide a signal to the motor 65 to rotate at a rate proportional to the extent or force with which the operator is retracting the firing trigger 20. This causes the motor 65 to rotate at a speed proportional to the signal from the sensor. The sensor is not shown for this embodiment, but it could be similar to the run motor sensor 110 described above. The sensor could be located in the handle 6 such that it is depressed when the firing trigger 20 is retracted. Also, instead of a proportional-type sensor, an on/off type sensor may be used.

Rotation of the motor 65 causes the bevel gears 66, 70 to rotate, which causes the planetary gear 72 to rotate, which causes, via the drive shaft 76, the ring gear 122 to rotate. The ring gear 122 meshes with the pinion gear 124, which is connected to the main drive shaft 48. Thus, rotation of the pinion gear 124 drives the main drive shaft 48, which causes actuation of the cutting/stapling operation of the end effector 12.

Forward rotation of the pinion gear 124 in turn causes the bevel gear 220 to rotate, which causes, by way of the rest of the gears of the gear box assembly 200, the first gear 210 to rotate. The first gear 210 engages the gear portions 206, 208 of the firing trigger 20, thereby causing the firing trigger 20 to rotate CCW when the motor 65 provides forward drive for the end effector 12 (and to rotate CCW when the motor 65 rotates in reverse to retract the end effector 12). In that way, the user experiences feedback regarding loading force and deployment of the end effector 12 by way of the user's grip on the firing trigger 20. Thus, when the user retracts the firing trigger 20, the operator will experience a resistance related to the load force experienced by the end effector 12. Similarly, when the operator releases the firing trigger 20 after the cutting/stapling operation so that it can return to its original position, the user will experience a CW rotation force from the firing trigger 20 that is generally proportional to the reverse speed of the motor 65.

It should also be noted that in this embodiment the user can apply force (either in lieu of or in addition to the force from the motor 65) to actuate the main drive shaft assembly (and hence the cutting/stapling operation of the end effector 12) through retracting the firing trigger 20. That is, retracting the firing trigger 20 causes the gear portions 206, 208 to rotate CCW, which causes the gears of the gear box assembly 200 to rotate, thereby causing the pinion gear 124 to rotate, which causes the main drive shaft 48 to rotate.

Although not shown in FIGS. 25-31, the instrument 10 may further include reverse motor and stop motor sensors. As described above, the reverse motor and stop motor sensors may detect, respectively, the end of the cutting stroke (full deployment of the knife/sled driving member 32) and the end of retraction operation (full retraction of the knife/sled driving member 32). A similar circuit to that described above in connection with FIG. 11 may be used to appropriately power the motor 65.

FIGS. 32-36 illustrate a two-stroke, motorized surgical cutting and fastening instrument 10 with power assist according to another embodiment. The embodiment of FIGS. 32-36 is similar to that of FIGS. 25-31 except that in the embodiment of FIGS. 32-36, the firing trigger 20 includes a lower portion 228 and an upper portion 230. Both portions 228, 230 are connected to and pivot about a pivot pin 207 that is disposed through each portion 228, 230. The upper portion 230 includes a gear portion 232 that engages the first gear 210 of the gear box assembly 200. The spring 222 is connected to the upper portion 230 such that the upper portion is biased to rotate in the CW direction. The upper portion 230 may also include a lower arm 234 that contacts an upper surface of the lower portion 228 of the firing trigger 20 such that when the upper portion 230 is caused to rotate CW the lower portion 228 also rotates CW, and when the lower portion 228 rotates CCW the upper portion 230 also rotates CCW. Similarly, the lower portion 228 includes a rotational stop 238 that engages a lower shoulder of the upper portion 230. In that way, when the upper portion 230 is caused to rotate CCW the lower portion 228 also rotates CCW, and when the lower portion 228 rotates CW the upper portion 230 also rotates CW.

The illustrated embodiment also includes the run motor sensor 110 that communicates a signal to the motor 65 that, in various embodiments, may cause the motor 65 to rotate at a speed proportional to the force applied by the operator when retracting the firing trigger 20. The sensor 110 may be, for example, a rheostat or some other variable resistance sensor, as explained herein. In addition, the instrument 10 may include a reverse motor sensor 130 that is tripped or switched when contacted by a front face 242 of the upper portion 230 of the firing trigger 20. When activated, the reverse motor sensor 130 sends a signal to the motor 65 to reverse direction. Also, the instrument 10 may include a stop motor sensor 142 that is tripped or actuated when contacted by the lower portion 228 of the firing trigger 20. When activated, the stop motor sensor 142 sends a signal to stop the reverse rotation of the motor 65.

In operation, when an operator retracts the closure trigger 18 into the locked position, the firing trigger 20 is retracted slightly (through mechanisms known in the art, including U.S. Pat. Nos. 6,978,921 and 6,905,057, which are incorporated herein by reference) so that the user can grasp the firing trigger 20 to initiate the cutting/stapling operation, as shown in FIGS. 32 and 33. At that point, as shown in FIG. 33, the gear portion 232 of the upper portion 230 of the firing trigger 20 moves into engagement with the first gear 210 of the gear box assembly 200. When the operator retracts the firing trigger 20, according to various embodiments, the firing trigger 20 may rotate a small amount, such as five degrees, before tripping the run motor sensor 110, as shown in FIG. 34. Activation of the sensor 110 causes the motor 65 to forward rotate at a rate proportional to the retraction force applied by the operator. The forward rotation of the motor 65 causes, as described above, the main drive shaft 48 to rotate, which causes the knife 32 in the end effector 12 to be deployed (i.e., begin traversing the channel 22). Rotation of the pinion gear 124, which is connected to the main drive shaft 48, causes the gears 210-220 in the gear box assembly 200 to rotate. Since the first gear 210 is in engagement with the gear portion 232 of the upper portion 230 of the firing trigger 20, the upper portion 232 is caused to rotate CCW, which causes the lower portion 228 to also rotate CCW.

When the knife 32 is fully deployed (i.e., at the end of the cutting stroke), the front face 242 of the upper portion 230 trips the reverse motor sensor 130, which sends a signal to the motor 65 to reverse rotational directional. This causes the main drive shaft assembly to reverse rotational direction to retract the knife 32. Reverse rotation of the main drive shaft assembly causes the gears 210-220 in the gear box assembly to reverse direction, which causes the upper portion 230 of the firing trigger 20 to rotate CW, which causes the lower portion 228 of the firing trigger 20 to rotate CW until the lower portion 228 trips or actuates the stop motor sensor 142 when the knife 32 is fully retracted, which causes the motor 65 to stop. In that way, the user experiences feedback regarding deployment of the end effector 12 by way of the user's grip on the firing trigger 20. Thus, when the user retracts the firing trigger 20, the operator will experience a resistance related to the deployment of the end effector 12 and, in particular, to the loading force experienced by the knife 32. Similarly, when the operator releases the firing trigger 20 after the cutting/stapling operation so that it can return to its original position, the user will experience a CW rotation force from the firing trigger 20 that is generally proportional to the reverse speed of the motor 65.

It should also be noted that in this embodiment the user can apply force (either in lieu of or in addition to the force from the motor 65) to actuate the main drive shaft assembly (and hence the cutting/stapling operation of the end effector 12) through retracting the firing trigger 20. That is, retracting the firing trigger 20 causes the gear portion 232 of the upper portion 230 to rotate CCW, which causes the gears of the gear box assembly 200 to rotate, thereby causing the pinion gear 124 to rotate, which causes the main drive shaft assembly to rotate.

The above-described embodiments employed power-assist user feedback systems, with or without adaptive control (e.g., using a sensor 110, 130, and 142 outside of the closed loop system of the motor, gear drive train, and end effector) for a two-stroke, motorized surgical cutting and fastening instrument. That is, force applied by the user in retracting the firing trigger 20 may be added to the force applied by the motor 65 by virtue of the firing trigger 20 being geared into (either directly or indirectly) the gear drive train between the motor 65 and the main drive shaft 48. In other embodiments of the present invention, the user may be provided with tactile feedback regarding the position of the knife 32 in the end effector, but without having the firing trigger 20 geared into the gear drive train. FIGS. 37-40 illustrate a motorized surgical cutting and fastening instrument with such a tactile position feedback system.

In the illustrated embodiment of FIGS. 37-40, the firing trigger 20 may have a lower portion 228 and an upper portion 230, similar to the instrument 10 shown in FIGS. 32-36. Unlike the embodiment of FIGS. 32-36, however, the upper portion 230 does not have a gear portion that mates with part of the gear drive train. Instead, the instrument includes a second motor 265 with a threaded rod 266 threaded therein. The threaded rod 266 reciprocates longitudinally in and out of the motor 265 as the motor 265 rotates, depending on the direction of rotation. The instrument 10 also includes an encoder 268 that is responsive to the rotations of the main drive shaft 48 for translating the incremental angular motion of the main drive shaft 48 (or other component of the main drive assembly) into a corresponding series of digital signals, for example. In the illustrated embodiment, the pinion gear 124 includes a proximate drive shaft 270 that connects to the encoder 268.

The instrument 10 also includes a control circuit (not shown), which may be implemented using a microcontroller or some other type of integrated circuit, that receives the digital signals from the encoder 268. Based on the signals from the encoder 268, the control circuit may calculate the stage of deployment of the knife 32 in the end effector 12. That is, the control circuit can calculate if the knife 32 is fully deployed, fully retracted, or at an intermittent stage. Based on the calculation of the stage of deployment of the end effector 12, the control circuit may send a signal to the second motor 265 to control its rotation to thereby control the reciprocating movement of the threaded rod 266.

In operation, as shown in FIG. 37, when the closure trigger 18 is not locked into the clamped position, the firing trigger 20 rotated away from the pistol grip portion 26 of the handle 6 such that the front face 242 of the upper portion 230 of the firing trigger 20 is not in contact with the proximate end of the threaded rod 266. When the operator retracts the closure trigger 18 and locks it in the clamped position, the firing trigger 20 rotates slightly towards the closure trigger 20 so that the operator can grasp the firing trigger 20, as shown in FIG. 38. In this position, the front face 242 of the upper portion 230 contacts the proximate end of the threaded rod 266.

As the user then retracts the firing trigger 20, after an initial rotational amount (e.g., 5 degrees of rotation) the run motor sensor 110 may be activated such that, as explained above, the sensor 110 sends a signal to the motor 65 to cause it to rotate at a forward speed proportional to the amount of retraction force applied by the operator to the firing trigger 20. Forward rotation of the motor 65 causes the main drive shaft 48 to rotate via the gear drive train, which causes the knife 32 and sled 33 to travel down the channel 22 and sever tissue clamped in the end effector 12. The control circuit receives the output signals from the encoder 268 regarding the incremental rotations of the main drive shaft assembly and sends a signal to the second motor 265 to caused the second motor 265 to rotate, which causes the threaded rod 266 to retract into the motor 265. This allows the upper portion 230 of the firing trigger 20 to rotate CCW, which allows the lower portion 228 of the firing trigger to also rotate CCW. In that way, because the reciprocating movement of the threaded rod 266 is related to the rotations of the main drive shaft assembly, the operator of the instrument 10, by way of his/her grip on the firing trigger 20, experiences tactile feedback as to the position of the end effector 12. The retraction force applied by the operator, however, does not directly affect the drive of the main drive shaft assembly because the firing trigger 20 is not geared into the gear drive train in this embodiment.

By virtue of tracking the incremental rotations of the main drive shaft assembly via the output signals from the encoder 268, the control circuit can calculate when the knife 32 is fully deployed (i.e., fully extended). At this point, the control circuit may send a signal to the motor 65 to reverse direction to cause retraction of the knife 32. The reverse direction of the motor 65 causes the rotation of the main drive shaft assembly to reverse direction, which is also detected by the encoder 268. Based on the reverse rotation detected by the encoder 268, the control circuit sends a signal to the second motor 265 to cause it to reverse rotational direction such that the threaded rod 266 starts to extend longitudinally from the motor 265. This motion forces the upper portion 230 of the firing trigger 20 to rotate CW, which causes the lower portion 228 to rotate CW. In that way, the operator may experience a CW force from the firing trigger 20, which provides feedback to the operator as to the retraction position of the knife 32 in the end effector 12. The control circuit can determine when the knife 32 is fully retracted. At this point, the control circuit may send a signal to the motor 65 to stop rotation.

According to other embodiments, rather than having the control circuit determine the position of the knife 32, reverse motor and stop motor sensors may be used, as described above. In addition, rather than using a proportional sensor 110 to control the rotation of the motor 65, an on/off switch or sensor can be used. In such an embodiment, the operator would not be able to control the rate of rotation of the motor 65. Rather, it would rotate at a preprogrammed rate.

The various embodiments of the present invention have been described above in connection with cutting-type surgical instruments. It should be noted, however, that in other embodiments, the inventive surgical instrument disclosed herein need not be a cutting-type surgical instrument. For example, it could be a non-cutting endoscopic instrument, a grasper, a stapler, a clip applier, an access device, a drug/gene therapy delivery device, an energy device using ultrasound, RF, laser, etc.

FIG. 43 depicts a surgical cutting and fastening instrument 2010 that is capable of practicing various unique benefits of the end effectors and drive arrangements of the present invention. The surgical instrument 2010 depicted in FIG. 43 comprises a handle 2006, a shaft assembly 2008, and an articulating end effector 2300 pivotally connected to the shaft assembly 2008 at an articulation pivot 2014. In various embodiments, the control handle houses a drive motor 2600 and control system generally represented as 2610 therein for controlling the opening and closing of the end effector 2300 and the cutting and stapling of the tissue clamped therein. An articulation control 2016 may be provided adjacent to the handle 2006 to effect rotation of the end effector 2300 about the articulation pivot 2014. The handle 2006 of the instrument 2010 may include a closure trigger 2018 and a firing trigger 2020 for actuating the end effector 2300. The end effector 2300 is shown separated from the handle 2006 preferably by an elongate shaft 2008. In one embodiment, a clinician or operator of the instrument 2010 may articulate the end effector 2300 relative to a proximal portion of the shaft 2008 by utilizing the articulation control 2016, as described in more detail in U.S. patent application Ser. No. 11/329,020, filed Jan. 10, 2006, entitled SURGICAL INSTRUMENT HAVING AN ARTICULATING END EFFECTOR, now U.S. Pat. No. 7,670,334. Other articulation arrangements could also be employed.

As will be discussed in further detail below, various end effector embodiments include an anvil 2340, which is maintained at a spacing that assures effective stapling and severing of tissue clamped in the end effector 2300. In various exemplary embodiments, the handle 2006 may include a pistol grip 2026 towards which a closure trigger 2018 is pivotally drawn by the clinician to cause clamping or closing of the anvil 2340 toward cartridge 2500 seated in an elongate channel 2302 of the end effector 2300 to thereby clamp tissue positioned between the anvil 2340 and the staple cartridge 2500. A firing trigger 2020 may be situated farther outboard of the closure trigger 2018. In various embodiments, once the closure trigger 2018 is locked in the closure position as further described below, the firing trigger 2020 may rotate slightly toward the pistol grip 2026 so that it can be reached by the operator using one hand. Then the operator may pivotally draw the firing trigger 2020 toward the pistol grip 2026 to cause the stapling and severing of clamped tissue in the end effector 2300. Those of ordinary skill in the art will readily appreciate however, that other handle and drive system arrangements may be successfully employed in connection with various embodiments described herein and their equivalent structures without departing from the spirit and scope of the present invention.

It will be appreciated that the terms “proximal” and “distal” are used herein with reference to a clinician gripping the handle 2006 of an instrument 2010. Thus, the end effector 2300 is distal with respect to the more proximal handle 2006. It will be further appreciated that, for convenience and clarity, spatial terms such as “vertical” and “horizontal” are used herein with respect to the drawings. However, surgical instruments are used in many orientations and positions, and these terms are not intended to be limiting and absolute.

FIGS. 43-47 illustrate a unique and novel end effector 2300 of various embodiments of the present invention adapted for use with a staple cartridge 2500, the basic operation of which is known in the art. For example, U.S. Pat. No. 6,978,921, entitled SURGICAL STAPLING INSTRUMENT INCORPORATING AN E-BEAM FIRING MECHANISM, provides more details about the construction of such staple cartridges.

In general, such staple cartridges 2500 include a cartridge body 2502 that is divided by a central, elongated slot 2508 which extends from the proximal end 2504 of the cartridge body 2502 towards its tapered outer tip 2506. See FIG. 46. The cartridge body 2502 may be fabricated from a polymeric material and be attached to a metal cartridge pan 2510. A plurality of staple-receiving pockets 2512 are formed within the cartridge body 2502 and are arranged in six laterally spaced longitudinal rows or “lines” of staples 2514, 2516, 2518, 2520, 2522, 2524. See FIG. 48. Positioned within the pockets 2512 are staple-supporting drivers 2532 which support staples 2534 thereon. Depending upon the location (line) of staple-receiving pockets 2512, the staple supporting drivers 2532 may support one or two staples 2530 thereon. The cartridge body 2502 further includes four longitudinal slots 2503, 2505, 2507, 2509 extending from its proximal end 2504 to its tapered outer tip 2506 for receiving corresponding sled cams 2328 formed on a wedge sled 2326 in the end effector 2300, the construction and operation of which will discussed in further detail below. See FIG. 47. As the sled cams 2328 are advanced through their respective slots 2503, 2505, 2507, 2509 in the cartridge body 2502 from proximal end 2504 to distal end 2506, they contact the staple-supporting drivers 2532 associated with those slots and force the staple-supporting drivers 2532 and the staples 2534 that they support upward out of the cartridge body 2502. See FIG. 49. As the ends of the legs 2536 of the staple 2534 contact the pockets 2350 formed in the bottom surface 2341 of the anvil 2340, they are folded over to close the staples 2534.

Various end effectors of the present invention include an elongate channel 2302 that is sized to removably receive and support the cartridge body 2502 and pan 2510 of a disposable cartridge 2500 therein. A knife screw 2304 is rotatably supported in the elongate channel 2302. The knife screw 2304 has a distal end 2306 that has a distal thrust bearing 2308 attached thereto that is rotatably supported by a distal bearing housing 2310 formed in the distal end 2303 of the elongate channel 2302. See FIG. 46. The knife screw 2304 has a central drive portion 2312 with a helical thread formed thereon. The knife screw 2304 further has a smooth extension portion 2314 and a knife screw gear 2316 formed thereon or otherwise attached thereto. A proximal thrust bearing 2318 is formed or attached to the proximal end 2317 of the knife screw 2304. The proximal thrust bearing 2318 is rotatably housed within a proximal bearing housing 2319 supported in a distal spine tube segment 2058. The distal spine tube segment 2058 has a pair of columns 2059 formed on its distal end that are adapted to be received in vertical slots 2307 formed in the proximal end 2305 of the elongate channel 2302. The columns 2059 may be retained within the slots 2307 in the elongate channel 2302 by friction, adhesive, or by the distal end of the shaft tube 2009. See FIGS. 43 and 46.

Various embodiments of the present invention further include a knife assembly 2320 that has a knife/sled bearing 2322 that is threaded onto the threaded portion 2312 of the knife screw 2304. The knife assembly 2320 supports a vertically extending blade 2324 and a wedge sled 2326 that supports the four sled cams 2328. The reader will understand that, as the knife screw 2304 is rotated in a clockwise direction, the knife assembly 2320 and the wedge sled 2326 is advanced toward the distal end 2303 (direction “A”) of the elongate channel 2302 and, when the knife screw 2304 is rotated in a counterclockwise direction, the knife assembly 2320 and wedge sled 2326 is moved toward the proximal end 2305 of the channel member 2302 (direction “B”). In addition, the knife assembly 2320 has a pair of laterally extending deflector tabs 2330 protruding therefrom, the purpose of which will be discussed below.

In various embodiments of the present invention, an anvil 2340 is pivotally coupled to the proximal end 2305 of the channel member 2302 by a pair of trunnion tabs 2342 that are sized to be received in oval-shaped pivot holes 2700 provided through the side walls 2309 of the elongate channel 2302. In various embodiments, the anvil 2340 may be stamped from sheet metal or other material such that the trunnion tabs 2342 are substantially rectangular or square shaped. In other embodiments, the anvil 2340 may be molded or machined from other materials such that it is rigid in nature and the trunnion tabs or pins are substantially round. As can be seen in FIGS. 49 and 73, the bottom surface 2341 of the anvil 2340 has a series of staple forming pockets 2350 formed therein. It will be understood that the staple forming pockets 2350 serve to close the staples 2534 as the ends of the staple legs 2536 are forced into contact therewith. In addition, a longitudinal clearance slot 2343 may be provided in the bottom surface 2341 of the anvil 2340 for receiving the upper end of the knife assembly 2320 and the guide tabs 2330 therethrough such that the laterally extending guide tabs 2330 serve to urge the anvil 2340 down onto the elongated channel 2302 as the knife assembly 2320 and wedge sled 2326 are driven through the cartridge 2500 to cut the tissue and deploy the staples 2534.

A drive assembly for operating various embodiments of the end effector 2300 will now be described. In various embodiments, a distal drive shaft portion 2402 extends through a drive shaft hole 2061 in the distal spine tube 2058. See FIG. 46. The distal drive shaft portion 2402 may extend directly to a drive motor arrangement 2600 in the control handle 2006 or it may be articulated to enable the end effector 2300 to be pivoted relative to the shaft or closure tube assembly that connects the end effector 2300 to the control handle 2006.

As can be seen in FIGS. 52-55, in various embodiments of the present invention the distal drive shaft portion 2402 has a clutch-receiving portion 2404 and a closure thread 2406 formed thereon. A clutch assembly 2410 is slidably received on the clutch-receiving portion 2404 of the drive shaft portion 2402. In various embodiments, the clutch assembly 2410 includes a collet-like tapered clutch member 2412 that has a drive gear 2414 integrally formed on its proximal end 2413. See FIGS. 56 and 57. The drive gear 2414 meshes with a transfer gear 2450 that in turn meshes with the knife screw gear 2316. See FIGS. 50 and 51. Thus, when the clutch assembly 2410 drivingly engages the distal drive shaft portion 2402, the drive gear 2414 rotates the transfer gear 2450 which, in turn rotates the knife screw gear 2316.

A series of four tapered sections 2416 are formed on the distal end 2415 of the tapered clutch member 2412. A series of male splines 2418 are formed in the interior of the tapered sections 2416. See FIGS. 56 and 57. The male splines 2418 are adapted to selectively engage a female spline section 2408 formed on the distal drive shaft portion 2402 as will be discussed in further detail below. See FIGS. 52-55. The clutch assembly 2410 further includes a clutch plate 2420 that is received on the tapered sections 2416 of the tapered clutch member 2412. As can be seen in FIGS. 58 and 59, the clutch plate 2420 has a proximal hub portion 2422 and a distal hub portion 2424 that is separated by a flange portion 2426. A cylindrical distal hole portion 2428 extends through the distal hub portion 2424 and a tapered proximal hole 2430 extends through the flange portion 2426 and the proximal hub portion 2422. The hole portions 2428, 2430 enable the clutch plate 2420 to be slidably received on the drive shaft 2402 and slide onto the tapered clutch member 2412. A clutch opening spring 2432 is provided between a flange portion 2417 formed on the tapered clutch member 2412 and the flange portion 2426 of the clutch plate 2420 and a thrust bearing 2434 is also journaled on the clutch-receiving portion 2404 adjacent to the clutch plate 2420. See FIGS. 63 and 64.

Also in various embodiments, a closure nut 2440 is received on the distal drive shaft portion 2402. As can be seen in FIGS. 54, 55, 60 and 61, the closure nut 2440 has a threaded hole portion 2442 extending partially therethrough to enable it to be threaded onto the closure thread 2406 on the distal drive shaft portion 2402. As can be further seen in those Figures, the closure nut 2440 has an upstanding closure ramp 2444 protruding therefrom. The top of the closure ramp 2444 terminates in a radiused portion 2446 that extends to an upstanding closure tab 2448 that is adapted to engage a downwardly protruding closure hook 2346 formed on the proximal end 2345 of anvil 2340.

More specifically and with reference to FIG. 63, the proximal end 2345 of the anvil 2340 has an anvil closure arm portion 2347 protruding proximally therefrom that terminates in a downwardly extending closure hook 2346. As can also be seen in that Figure, the bottom surface of the anvil closure arm 2347 has a tab relief groove 2348 therein for receiving the closure tab 2348 when the closure nut 2440 is advanced to its most distal position (shown in FIGS. 69-72). Also in various embodiments, a closure lock spring 2460 is attached to the bottom of the elongate channel 2302, by mechanical fastener arrangements or adhesive. The closure lock spring 2460 has an upper portion 2462 that terminates in an upstanding retainer lip 2464. In addition, longitudinally extending retainer arm 2466 is rigidly attached to the upper portion 2462 of the closure lock spring 2460. See FIG. 46.

Various embodiments of the present invention employ an anvil 2340 that is capable of moving axially and laterally relative to the elongate channel 2302 prior to being advanced to the closed position. More specifically and with reference to FIGS. 62-72, in various embodiments, the elongate channel 2302 is stamped or otherwise formed from sheet metal or the like and the pivot holes may be punched therein. Such construction leads to reduced manufacturing costs for the end effector. Other embodiments may be machined from rigid materials such as 2416 stainless steel such that the trunnion pins are substantially round in cross-section. Regardless of which manufacturing method is employed to manufacture the anvil 2340 and the resulting shape of the trunnion tabs 2342, as can be seen in FIGS. 63, 66, 68, 70, and 74, the pivot holes 2700 are oval or oblong and serve to afford the trunnion tabs 2342 with the ability to move axially back and forth and up and down in their corresponding pivot hole 2700. As can be seen in FIG. 74, the trunnion tabs 2342 may have a length “X” of, for example, approximately 0.060 inches and a height “Y” of, for example, approximately 0.050 inches. The pivot holes 2700 have a proximal wall portion 2702, a distal wall portion 2704, an upper wall portion 2706 and a lower wall portion 2708. In various embodiments, for example, the distance “L” between the proximal wall 2702 and the distal wall 2704 may be approximately 0.120 inches and the distance “H” between the upper wall portion 2706 and lower wall portion 2708 may be approximately 0.090 inches. See FIG. 74. Those of ordinary skill in the art will appreciate that these distances and tolerances may, in connection with various embodiments, be somewhat dictated by the manufacturing tolerances attainable by the processes used to manufacture the anvil 2340 and the elongate channel 2302. In other embodiments, however, the distances “H”, “L”, “X”, and “Y” may be sized relative to each other to enable the anvil 2340 to travel along a closing path that is relatively substantially parallel to the top surface of a cartridge 2500 supported in the elongate channel 2302. Such arrangement serves to prevent or minimize the likelihood of tissue from being rolled out of between the anvil and the cartridge during clamping. Thus, these dimensions are merely exemplary and are not intended to be limiting. The trunnion tabs 2342 and the pivot holes 2700 may have other sizes, shapes and dimensions relative to each other that differ from such exemplary dimensions given herein that nevertheless enable those components to operate in the unique and novel manner of various embodiments of the present invention as described herein.

This ability of the trunnion tabs 2342 to travel within their respective pivot hole 2700 in the side walls of the 2309 of the elongate channel 2302 can be appreciated from reference to FIGS. 62-68. As can be seen in each of those Figures, the closure nut 2440 is in its distal-most open position. When in that position, the retainer lip 2464 of the closure lock spring is biased under the closure nut 2440 and does not restrict the travel thereof. FIGS. 62 and 63 illustrate the trunnion tabs 2342 adjacent the proximal end wall portions 2702 of the pivot holes. FIGS. 65 and 44 illustrate the trunnion tabs 2342 after they have crept somewhat midway between the proximal end wall portion 2702 and the distal end wall portion 2704 of the pivot hole 2700. FIGS. 67 and 68 illustrate the trunnion tabs 2342 after they have crept to a position adjacent the distal end wall portions 2704 of the pivot holes 2700. Thus, in various embodiments, the trunnion tabs 2342 are loosely received within their respective pivot holes 2700 and capable of moving axially, laterally and vertically or in combinations of such directions therein.

FIGS. 69-72 illustrate the anvil 2340 in a closed position. As can be seen in FIG. 70, the trunnion tabs 2342 are in abutting contact with a proximal end wall portion 2702 of the pivot hole 2700. When in that position (i.e., when the trunnion tabs 2342 are held in abutting contact with proximal end wall portion 2702), the staple-forming pockets 2350 in the bottom surface 2341 of the anvil 2340 are in axial registration with corresponding staple-receiving pockets 2512 in the cartridge 2500 seated in the elongate channel 2302 such that when the staples 2534 are fired, they are correctly formed by the corresponding pockets 2350 in the anvil 2340. The anvil 2340 is locked in that position by the retainer lip 2464 portion of the closure lock spring 2460 as will be discussed in further detail below.

Also in various embodiments, the anvil 2340 is capable of moving laterally relative to the elongate channel due to manufacturing tolerances in the fabrication of the trunnion tabs 2342 and the pivot holes 2700. As can be seen in FIGS. 44-46, 62, 65, 69, and 73, in various embodiments, the anvil 2340 is provided with a pair of downwardly extending tissue stops 2344. During the clamping process, the tissue stops 2344 essentially perform two functions. One of the functions consists of orienting the tissue 2900 within the end effector 2300 so as to prevent the tissue 2900 from extending axially into the end effector 2300 such that it extends beyond the innermost staple pockets 2512 in the cartridge 2500 when seated in the elongate channel 2302. See FIG. 65. This prevents tissue 2900 from being cut that is not stapled. The other function performed by the tissue stops 2344 is to axially align the anvil 2340 relative to the elongate channel 2302 and ultimately to the cartridge 2500 received therein. As the anvil 2340 is closed, the tissue stops 2344 serve to contact corresponding alignment surfaces 2720 on the side of the elongate channel 2302 and serve to laterally align the anvil 2340 relative to the elongate channel 2302 when the anvil 2340 is closed and clamping tissue 2900 such that the staple-forming pockets 2350 in the bottom surface 2341 of the anvil 2340 are laterally aligned with the corresponding staple-receiving pockets 2512 in the cartridge 2500. See FIGS. 69 and 73.

The operation of various embodiments of the present invention will now be described with reference to FIGS. 62-71. FIGS. 62-68 illustrate the closure nut 2440 in an open position. As can be seen in those Figures, when in the open position, the closure nut 2440 is located such that the hook arm 2346 is permitted to move to various positions relative thereto that enable the anvil 2340 to pivot open to permit tissue 2900 to be inserted between the anvil 2340 and the elongated channel 2302 and cartridge 2500 seated therein. When in this position, the distal end 2467 of the retainer arm 2466 that is attached to the closure lock spring 2460 is in contact with a ramp surface 2321 formed on the proximal end of the knife assembly 2320. See FIG. 64. As the knife assembly 2320 moves proximally, the end of the retainer arm 2466 contacts the ramp surface 2321 on the proximal end of the knife assembly 2320 and serves to cause the retainer arm 2466 to bias the upper portion 2462 of the closure lock spring 2460 downward toward the bottom of the elongate channel 2302. When the knife assembly 2320 moves distally away from the retainer arm 2466, the upper portion 2462 of the closure lock spring 2460 is permitted to spring upward to enable the retainer lip 2464 to engage the closure nut 2440 as will be further discussed below.

The reader will appreciate that when the end effector 2300 is in the open positions depicted in FIGS. 62-68, the user can install a disposable cartridge assembly 2500 in the elongate member 2302. Also, when in those positions, the anvil 2340 may be able to move axially, laterally and vertically relative to the elongate channel 2302. In various embodiments, when the drive shaft 2402 is rotated in a first direction, the closure thread 2406 thereon threadably drives the closure nut 2440 in the proximal direction (direction “B” in FIG. 50) until the closure threads 2406 disengage the threaded hole 2442 in the closure nut 2440. See FIG. 55. As the closure nut 2440 is driven proximally, the closure hook 2346 on the anvil closure arm 2347 rides up the ramp 2444 of the closure nut 2440 until it rides into the radiused portion 2446 and contacts the closure tab 2448. Such movement of the closure nut 2440 serves to “pull” the anvil 2340 to the closed position. See FIGS. 69-71. When in that position, the trunnion tabs 2342 are in abutting contact with the proximal end portion 2702 of the pivot holes 2700 and the retainer lip 2464 of the closure lock spring has engaged the distal end 2441 of the closure nut 2440 to retain the anvil 2340 in the fully closed and axially aligned position. When also in that position, by virtue of the contact of the tissue stops 2344 with the alignment surfaces 2720 on the side walls 2309 of the elongate channel 2302, the anvil 2340 is laterally aligned with the elongate channel 2302 so that the staple forming pockets 2350 in the anvil 2340 are laterally aligned with corresponding the staple-receiving pockets 2512 in the cartridge 2500.

As the closure nut 2440 is driven in the proximal direction, the proximal end 2449 of the closure nut 2440 contacts the thrust bearing 2434 which forces the clutch plate 2420 in the proximal direction against the force of clutch opening spring 2432. Further travel of the closure nut 2440 in the proximal direction drives the clutch plate 2420 onto the tapered sections 2416 of the tapered clutch member 2412 which causes the male splines 2418 therein to engage the female splines 2408 on the distal drive shaft portion 2402. Such engagement of the male splines 2418 in the tapered clutch member 2412 with the female splines on the distal drive shaft portion 2402 causes the tapered clutch member 2412 and the drive gear 2414 to rotate with the distal drive shaft portion 2402. Drive gear 2414, in turn, rotates the knife screw gear 2316 which causes the knife screw to rotate and drive the knife assembly distally (“A” direction).

As the knife assembly 2320 is driven distally, it cuts the tissue and the cams 2328 on the wedge sled 2326 serve to drive the staple supporting drivers 2532 upward which drive the staples 2534 toward the anvil 2340. As the legs 2536 of the staples 2534 are driven into the corresponding staple-forming pockets 2350 in the anvil 2340, they are folded over. See FIG. 49.

When the knife assembly 2320 moves distally, the distal end 2467 of the retainer arm 2466 is no longer in contact with the ramp surface 2321 of the knife assembly 2320 which enables the retainer arm 2466 and the upper portion 2462 of the closure lock spring 2460 to spring upwardly which further enables the retainer lip 2464 on the closure lock spring 2460 to retainingly engage the distal end 2441 of the closure nut 2440 to prevent it from moving distally. See FIGS. 70 and 71. By virtue of its contact with the closure nut 2440 which is in contact with the thrust bearing 2434, the retainer lip 2464 serves to retain the clutch assembly 2410 engaged with the distal drive shaft portion 2402 until the knife assembly 2320 once again returns to contact the distal end 2467 of the retainer arm 2464. After the knife assembly 2320 has been driven to its final distal position as shown in FIG. 72, it activates a conventional sensor or contact 2313 mounted within the elongate channel 2302 and signals the control motor to stop driving the drive shaft 2402. See FIG. 76. Those of ordinary skill in the art will understand that a variety of different control arrangements could be employed to control the drive shaft 2402. For example, when the knife assembly 2310 reaches its distal-most position and activates the sensor 2313, the control system 2610 housed within the handle 2006 could automatically reverse the drive motor 2600 therein and cause the drive shaft portion 2402 and knife screw to reverse direction (e.g., move in the proximal “B” direction). In various other embodiments, the control system 2610 may simply stop the drive motor 2600 and then require the surgeon to activate a button 2030 to cause the motor 2600 to reverse. In still other arrangements, the control system 2610 may institute a predetermined timed delay between the time that the reversing sensor 2313 is activated and the time that the motor 2600 is reversed.

As the knife assembly 2320 moves in the proximal direction on the knife screw 2304, the closure threads 2406 on the drive shaft 2402 begin to screw back into the threaded hole portion 2442 in the closure nut 2440. During this process, the ramp surface 2321 of the knife assembly 2320 again contacts the distal end 2467 of the retainer arm 2466 which serves to bias the upper portion 2462 of the closure lock spring 2460 toward the bottom of the elongate channel 2302 to permit the retainer lip 2464 to disengage from the distal end 2441 of the closure nut 2440 thereby permitting the clutch opening spring 2432 to bias the clutch assembly 2410 and closure nut 2440 distally. As the closure nut 2440 moves distally, the closure hook 2346 on the anvil 2340 rides up the ramp 2444 on the closure nut 2440 until the closure nut 2440 reaches the open position wherein the closure tab 2448 is received within the tab relief groove 2348 in the bottom surface 2341 of the anvil 2340 and the closure nut 2440 moves the anvil assembly 2372 to the open position. A second conventional sensor or contact 2315 is mounted within the proximal end portion 2305 of the elongate channel 2302 for sensing when the closure nut 2440 is in the open position and communicates with the motor to cause it to stop. See FIG. 46.

As indicated above, a variety of different motor/control arrangements may be employed to power the drive shaft portion 2402. For example, in various embodiments when the closure trigger 2018 is actuated, that is, drawn in by a user of the instrument 2010, the motor 2600 may commence the above described closing process. A third sensor 2315′ may be used in the elongate channel member 2302 to sense when the closure nut 2404 has moved into the closed position (shown in FIG. 70). When the third sensor 2315′ senses that the closure nut 2440 is in that position, the sensor 2315′ may cause the motor 2600 to stop rotating. Thereafter, if the surgeon is satisfied with the clamping of the tissue in the end effector 2300, the surgeon may actuate the firing trigger 2020 or other actuator arrangement to activate the motor 2600 to rotate the drive shaft 2402 which drives the knife screw 2304 in the above-mentioned manner.

Another drive arrangement is depicted in FIGS. 75-77. In this embodiment, a closure wedge 2440′ is axially moved by a manual drive assembly 2800. More specifically and with reference to FIG. 75, the proximal end 2802 of the drive shaft 2402′ is has a drive gear 2810 attached thereto. Although a variety of different gear and motor arrangements may be employed, the drive gear 2810 may be oriented for selective meshing engagement with a gear train or transmission assembly generally designated as 2820 that is ultimately driven my motor 2600. The drive shaft 2402′ is movably supported by a proximal spine tube segment 2820 that is pivotally coupled to the distal spine tube segment 2058 as described in various of the U.S. patent applications incorporated by reference herein above and rigidly attached to the housing portions 2007 of the handle 2006. In other arrangements wherein the end-effector is not capable of articulating travel, the distal spine tube 2058 may be longer and rigidly coupled to the sections 2007 of the handle 2006. Regardless of which spine tube arrangement is employed, the drive shaft 2402′ is axially and rotatably received therein such that the drive shaft 2402′ can move axially in the distal and proximal directions and also rotate when engaged with the motor 2600.

Various methods may be employed to mechanically move the drive shaft 2402′ in the distal and proximal directions. For example, as shown in FIG. 75, a thrust bearing assembly 2830 may be attached to the drive shaft 2402′ for selective contact by a control linkage assembly 2840. As can be seen in that Figure, the control linkage assembly 2840 may be linked to the closure trigger 2018 and capable of biasing the drive shaft 2402′ in the proximal (“B”) direction when the closure 2018 is pivoted in the proximal direction, the control linkage assembly contacts the thrust bearing and pulls the drive shaft 2402 in the proximal direction.

Turning next to FIGS. 76 and 77, as can be seen in these Figures, the distal end 2406′ of the drive shaft is rotatably supported within a closure wedge 2440′ that is similar in construction as closure nut 2440 as described above. In particular, the closure wedge 2440′ has a proximal hole 2442′ and a distal hole portion 2443′ that is larger in diameter than the proximal hole portion 2442′. The distal end 2406′ of the drive shaft 2402′ is rotatably supported in the distal hole portion 2443′by a bearing 2445′. The distal end portion 2406′ of the drive shaft 2406′ is longer than the hole 2403′ such that as the drive shaft 2402′ moves distally and proximally, it cannot become disengaged from the wedge 2440′. The wedge 2440′ also has a closure ramp portion 2444′, a radiused portion 2446′, and a closure tab 2448′ formed thereon. As can be seen in FIGS. 76 and 77, a drive gear 2414′ is attached to the drive shaft 2402′ and is adapted to mesh with the transfer gear 2450 that is in meshing engagement with the knife screw gear 2316.

In these embodiments, when the user wishes to close the anvil 2340, the user moves the closure trigger 2018 toward the handle 2006. This action causes the control linkage assembly 2840 to move the drive shaft 2402′ in the proximal direction and pull the wedge 2440′ proximally. As the wedge 2440′ moves proximally, the closure hook 2346 on the proximal end 2345 of the anvil 2340 rides up the ramp portion 2444′ thereon until the it is seated in the radiused portion 2446′ of the wedge 2440′. The wedge 2440′ gets biased proximally until the retainer lip 2464 engages the distal end 2441′ of the wedge 2440′ as shown in FIG. 77. When in that position, the trunnion tabs 2342 of the anvil 2340 are in engagement with the proximal end portion 2702 of pivot holes 2700 as described above. Also when in that position, the drive gear 2414′ is now in meshing engagement with the transfer gear 2450 (not shown in FIG. 77) that is in meshing engagement with the knife screw gear 2316. Thus, when the drive shaft 2402′ is rotated by activating the control motor, the drive gear 2414′ serves to drive the transfer gear 2450 and the knife screw gear 2316 to drive the knife assembly 2320 in the above described manner. The closure lock spring 2460 and the motor control sensors in the elongate channel operate in the above described manner.

After the drive motor 2600 has reversed the rotation of the drive shaft 2402′ which drives the knife assembly 2320 proximally back to its starting position wherein the ramp surface 2321 contacts the distal end 2467 of the retainer arm 2466, the lip 2464 of the closure lock spring 2460 is biased downwardly to permit the wedge 2440′ to move distally. The user can then release the closure trigger 2018 which is spring biased to the unactuated position shown in FIG. 43. As the closure trigger 2018 returns to the unactuated position, the control linkage assembly 2840 permits the drive shaft 2402′ and wedge 2440′ to move distally and open the anvil 2340 in the above-described manner.

The reader will understand that various embodiments of the present invention provide vast improvements over prior end effectors and end effector drive arrangements. In particular, the various unique and novel drive system of various embodiments of the present invention permit the anvil and elongated channel components of the end effector to be manufactured utilizing materials and processes that are more economical than other materials and processes used in the past without sacrificing performance. In addition, by providing an anvil that can travel along a closing path that is substantially parallel to the elongate channel and staple cartridge housed therein, reduces the likelihood that the tissue will be rolled out of position during the initial closing of the anvil.

The invention which is intended to be protected is not to be construed as limited to the particular embodiments disclosed. The embodiments are therefore to be regarded as illustrative rather than restrictive. Variations and changes may be made by others without departing from the spirit of the present invention. Accordingly, it is expressly intended that all such equivalents, variations and changes which fall within the spirit and scope of the present invention as defined in the claims be embraced thereby.

Although the present invention has been described herein in connection with certain disclosed embodiments, many modifications and variations to those embodiments may be implemented. For example, different types of end effectors may be employed. Also, where materials are disclosed for certain components, other materials may be used. The foregoing description and following claims are intended to cover all such modification and variations.

Any patent, publication, or other disclosure material, in whole or in part, that is said to be incorporated by reference herein is incorporated herein only to the extent that the incorporated materials does not conflict with existing definitions, statements, or other disclosure material set forth in this disclosure. As such, and to the extent necessary, the disclosure as explicitly set forth herein supersedes any conflicting material incorporated herein by reference. Any material, or portion thereof, that is said to be incorporated by reference herein, but which conflicts with existing definitions, statements, or other disclosure material set forth herein will only be incorporated to the extent that no conflict arises between that incorporated material and the existing disclosure material. 

What is claimed is:
 1. A surgical cutting and fastening instrument comprising: an end effector comprising a moveable cutting instrument for cutting an object positioned in the end effector; a main drive shaft assembly connected to the end effector; a gear drive train connected to the main drive shaft assembly; a main motor for actuating the gear drive train; a firing trigger for actuating the main motor; and a tactile position feedback system for applying force to the firing trigger such that the position of the firing trigger is related to the position of the cutting instrument in the end effector.
 2. The surgical cutting and fastening instrument of claim 1, wherein the tactile position feedback system includes: an encoder for sensing rotation of the main drive shaft assembly; a second motor whose rotations are controlled based on the rotations main drive shaft assembly sensed by the encoder; and an actuating member connected to the second motor, wherein the actuating member is for applying the force to the firing trigger such that position of the firing trigger is related to the position of the cutting instrument in the end effector.
 3. The surgical cutting and fastening instrument of claim 2, wherein the actuating member includes a threaded rod.
 4. The surgical cutting and fastening instrument of claim 2, further comprising a run motor sensor for sensing retracting of the firing trigger, wherein, when retraction of the firing trigger is sensed by the run motor sensor, the main motor is signaled to forward rotate to cause cutting of the object positioned in the end effector by the cutting instrument.
 5. The surgical cutting and fastening instrument of claim 4, wherein the run motor sensor comprises a proportional switch such that the rate of rotation of the main motor is proportional to the retraction force applied to the firing trigger.
 6. The surgical cutting and fastening instrument of claim 4, wherein the run motor sensor comprises an on/off switch.
 7. The surgical cutting and fastening instrument of claim 4, further comprising a control circuit for receiving signals from the encoder related to rotation of the main drive shaft assembly and for sending control signals to the second motor based on the signals received from the encoder.
 8. The surgical cutting and fastening instrument of claim 7, wherein the control circuit is further for: determining, based on the signals received from the encoder, when the cutting instrument has completed a cutting stroke; and determining, based on the signals received from the encoder, when the cutting instrument has completed retraction.
 9. The surgical cutting and fastening instrument of claim 1, wherein the end effector includes a staple cartridge.
 10. The surgical cutting and fastening instrument of claim 1, wherein the end effector includes a helical drive screw, such that forward rotation of the helical drive screw causes the cutting instrument to undertake the cutting stroke, and reverse rotation of the helical drive screw causes the cutting instrument to retract.
 11. The surgical cutting and fastening instrument of claim 1, wherein the main drive shaft assembly includes articulation means for articulating the end effector.
 12. The surgical cutting and fastening instrument of claim 1, further comprising a closure trigger separate from the firing trigger, wherein retraction of the closure trigger causes the end effector to clamp the object positioned in the end effector.
 13. The surgical cutting and fastening instrument of claim 12, further comprising a locking mechanism for locking the closure trigger to the handle.
 14. The surgical cutting and fastening instrument of claim 12, further comprising a mechanical closure system for closing the end effector when the closure trigger is retracted.
 15. The surgical cutting and fastening instrument of claim 14, wherein the end effector comprises: an elongate channel for carrying the cutting instrument; and a clamping member pivotably connected to the elongate channel.
 16. The surgical cutting and fastening instrument of claim 15, wherein the mechanical closure system includes: a yoke connected to the closure trigger; a closure bracket connected to the yoke; a closure tube disposed in the closure bracket and connected to the clamping member, wherein retraction of the closure trigger causes the closure tube to move longitudinally such that the clamping member pivots to a clamped position.
 17. A surgical cutting and fastening instrument comprising: an end effector comprising a moveable cutting instrument for cutting an object positioned in the end effector; a main drive shaft assembly connected to the end effector; and a handle connected to the main drive shaft assembly, wherein the handle comprises: a gear drive train connected to the main drive shaft assembly; a main motor for actuating the gear drive train; a firing trigger for actuating the main motor; and a tactile position feedback system for applying force to the firing trigger such that position of the firing trigger is related to the position of the cutting instrument in the end effector; and a run motor sensor for sensing retracting of the firing trigger, wherein, when retraction of the firing trigger is sensed by the run motor sensor, the main motor is signaled to forward rotate to cause cutting of the object positioned in the end effector by the cutting instrument.
 18. The surgical cutting and fastening instrument of claim 17, wherein the run motor sensor comprises a proportional switch such that the rate of rotation of the main motor is proportional to the retraction force applied to the firing trigger.
 19. The surgical cutting and fastening instrument of claim 18, wherein the end effector comprises: an elongate channel for carrying the cutting instrument; and a clamping member pivotably connected to the elongate channel.
 20. A surgical cutting and fastening instrument comprising: an end effector comprising a moveable cutting instrument for cutting an object positioned in the end effector. a main drive shaft assembly connected to the end effector; and a handle connected to the main drive shaft assembly, wherein the handle comprises: a gear drive train connected to the main drive shaft assembly; a main motor for actuating the gear drive train; a firing trigger for actuating the main motor; and means for applying force to the firing trigger such that position of the firing trigger is related to the position of the cutting instrument in the end effector. 